"Fabric protection" for new furniture - yea or nay?

There comes that time when buying new furniture, near the end of the transaction, where they show you the "examples" of treated vs. non-treated fabric and you need to make the choice whether to add this for $150-200, or abstain.

I'm sure some may say make that choice relative to the amount of purchase you are making and the use of the piece of furniture as well as other factors - pets, young kids, etc.

Bottom line, does this stuff work? Do they honor the warranty? Is the fabric treated anyway? I read it cost them ~$5 to treat a sofa.

I choose to abstain with no young children, no pets on sofa and expecting a 7-8 year life of daily use.